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 * Version: CPL 1.0/GPL 2.0/LGPL 2.1
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 * Copyright (C) 2006 Tim Azzopardi <tim@tigerfive.com>
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package org.jruby.environment;

import java.util.Map;

import org.jruby.Ruby;

public interface IOSEnvironmentReader {

	/**
	 * Get the operating system environment variables.
     * 
     * Returns an string map view of the current system environment. 
     * If environment variables,are not supported, then null is returned.  (isEnvironmentAccessible() returns false).
     * If there are no variables defined, then an empty Map is returned. 
	 * 
	 * @return the operating system environment variables in a Map<String,String>.
     * @throws OSEnvironmentReaderExcepton if there is a problem accessing the environment variables.
	 */
	Map getVariables(Ruby runtime);

    /**
     * Determines whether the OS environment variables are accessible using a given implementation.
     * 
     * @return  whether the OS environment variables are accessible.
     */
    boolean isAccessible(Ruby runtime);;

}